Synthesis of symmetrical structured triglycerides via a bottom-up process

The synthesis of symmetrical structured triglycerides (STG) through a bottom-up approach was previously shown to produce 1,3-dioleoyl-2-palmitoyl glycerol in significant quantities. This solvent-free lipase-catalyzed process, consisting of a low-temperature (40 °C) esterification step with glycerol dosing followed by a high-temperature (60 °C) esterification step, was further investigated in the production of symmetrical medium-and-long-chain triglycerides (MLCT). By replacing oleic acid with capric acid in the first step or the palmitic acid by either capric acid or lauric acid in the second step, the effects of free fatty chain length and sequence of fatty acid addition on STG production were established. These produced 1,3-dicaproyl-2-oleoyl glycerol, 1,3-dioleoyl-2-caproyl glycerol, and 1,3-dioleoyl-2-lauroyl glycerol at concentrations of 36.98 g, 36.77 g, and 37.08 g per 100 g of triglycerides respectively after 72 h at an overall FFA1:FFA2:Glycerol of 2:1:1 and 4 g Novozyme 435 per 100 g reactants, without the purification of intermediates and products. The sequence of fatty acid addition had the most significant effect as purer STG products can be obtained when the medium chain fatty acid is introduced in the first step. As the process was carried out without solvents, the STG produced are appropriate for functional food or nutraceutical applications.

Beneficial Effects of Akkermansia muciniphila Are Not Associated with Major Changes in the Circulating Endocannabinoidome but Linked to Higher Mono-Palmitoyl-Glycerol Levels as New PPARα Agonists

Akkermansia muciniphila is considered as one of the next-generation beneficial bacteria in the context of obesity and associated metabolic disorders. Although a first proof-of-concept of its beneficial effects has been established in the context of metabolic syndrome in humans, mechanisms are not yet fully understood. This study aimed at deciphering whether the bacterium exerts its beneficial properties through the modulation of the endocannabinoidome (eCBome). Circulating levels of 25 endogenous endocannabinoid-related lipids were quantified by liquid chromatography with tandem mass spectrometry (LC-MS/MS) in the plasma of overweight or obese individuals before and after a 3 months intervention consisting of the daily ingestion of either alive or pasteurized A. muciniphila. Results from multivariate analyses suggested that the beneficial effects of A. muciniphila were not linked to an overall modification of the eCBome. However, subsequent univariate analysis showed that the decrease in 1-Palmitoyl-glycerol (1-PG) and 2-Palmitoyl-glycerol (2-PG), two eCBome lipids, observed in the placebo group was significantly counteracted by the alive bacterium, and to a lower extent by the pasteurized form. We also discovered that 1- and 2-PG are endogenous activators of peroxisome proliferator-activated receptor alpha (PPARα). We hypothesize that PPARα activation by mono-palmitoyl-glycerols may underlie part of the beneficial metabolic effects induced by A. muciniphila in human metabolic syndrome.

Sulfoquinovosyl oleoyl palmitoyl glycerol (SQDG) and hexane extract of Sargassum plagyophylum prevent depression induced by dexamethasone or stress in mice

Introduction: M Glucocorticoids and stress are a leading cause of depression by dysregulation of hypothalamic hypophyseal adrenal axis. Sargassum plagyophylum hexane extract (HxE) has proven antidepressant-like effects in mice. We aimed at evaluating HxE and sulfoquinovosyl oleoyl palmitoyl glycerol (SQDG) isolated compound antidepressant effects following dexamethasone (Dex) or water avoidance stress (WAS) induced depression in mice. Methods: The HxE was prepared and fractionated by different chromatography methods to isolate active compounds. Depression was induced in male mice by Dex single dose or by four days of WAS. After the locomotor test, depression was assessed by measuring the immobility time during the forced swimming test (FST) and sucrose preference test. Results: 6-Deoxy-6-sulpho-α-D-glucopyranosyl-1,2-O-diacyl-glycerol was isolated and elucidated from the seaweed. The manipulations did not cause important changes in animals’ locomotor activity. During FST, immobility time increased dramatically by Dex (193 ± 13 s vs control 109 ± 7 s) or WAS (189 ± 13 s vs sham 86 ± 14 s), that indicated depression. HxE 40 mg/kg reduced the immobility time when it was administered with Dex (110 ± 28 s, P < 0.01 vs Dex alone) or together with WAS (86 ± 11 s, P < 0.001 vs WAS). SQDG 40 mg/kg reduced the immobility time when co-administered with Dex (22 ± 9 s, P < 0.001 vs Dex alone) and when it was administered along with WAS (68 ± 16 s, P < 0.001 vs WAS). The results of the sucrose preference test were in line with FST results as sucrose preference below 65% was considered for anhedonia. Conclusion: SQDG and probably the steroid content in S. plagyophylum HxE prevented depression in mice; thus, they should be considered for further clinical evaluations.

Removal of Triolein Lipid From Aqueous System by Molecularly Imprinted Chitosan and Its Derivative

Chitosan was molecularly imprinted to remove triolein (a model lipid triacylglyceride) from water. Molecularly-imprinted chitosan (chitosan-MIP) was synthesized by crosslinking it with glutaraldehyde in the presence of triolein as the template at 50°C for 2h. MIPs of octanoyl derivative of chitosan(Oct-MIP) were also prepared by similar method. Octanoyl chitosan was synthesized by N-acylation of chitosan using octanoyl chloride at room temperature for 12h. Contact angle measurements of water droplet on chitosan and octanoyl chitosan revealed increased hydrophobicity of octanoyl derivative of chitosan. FTIR spectroscopy was used to characterize the derivative and the MIPs. All the synthesized polymers. Oct-MIP and chitosan-MIP could imprint approximately 77% and 66% of triolein template, respectively. Binding experiments revealed that Oct-MIP exhibit higher triolein binding capacity than corresponding non-acylated polymers. In 6h, 1mg of Oct-MIP and chitosan-MIP could rebind 534.50µg and 380.35µg of triolein respectively. Non Imprinted octanoyl chitosan and chitosan bound 272µg and 198.24µg triolein respectively. Both types of MIPs could also bind a triolein analog (1,3-dioleoyl-2-palmitoyl glycerol).

Chemoenzymatic Solvent-free Synthesis of 1-Monopalmitin Using a Microwave Reactor

An environmentally friendly method for the synthesis of 1-monopalmitin has been developed. The procedure consists of a two-step, solvent-free chemoenzymatic reaction. In the first step, palmitic acid is esterified with solketal (4-hydroxymethyl-2,2-dimethyl-1,3-dioxolane) using Novozym 435 by both conventional heating and microwave irradiation. The use of a microwave reactor allows the enzymatic synthesis of the intermediate compound with a similar yield as that achieved using conventional heating. In the second step, 1,2-acetonide-3-palmitoyl glycerol is cleaved to yield 1-monopalmitin by means of a cation-exchange resin and water or aliphatic alcohols as hydrolytic reagent in solvent-free conditions. The hydrolysis was accomplished in 15 min at 85°C. The best yield was obtained using 1-pentanol. We conclude that the yield achieved depends on the batch and nature of the cation-exchange resin used as catalyst.